Enlarge wastegate hole?

[Spl170s]

jsut wanted some opinions.....

TE Turbo. Measured the hole on the exhaust housing.... 1" dia

The puck on the DP is 1 3/8 dia. Jsut about centered...only off maybe less than a 1/16 to one side of the hole. averaging about 3/16 left for puck to seat against.

I really, really don't want to port this if i don't have too. i don't care for dremeling on the exhaust housing with the turbo on the car, and taking it off is not looking to fun either.

Been having boost creep issues... figured this was it...but i am not seeing much to make me think i need to cut on it.

opinions??

 

[2QUIK6]

I had the same problem with a GT61, you'd be surprised how much better it will controll boost with it opened up just 1/16". With the puck not centered over the hole already you'll have no choice but to do it with a dremmel unless you have access to a mill machine. Be sure to mark where the puck contacts the exhaust housing and then do not cross that mark when dremmeling. Mine is less than 1/32 on one side...I also had to smooth out the inside radius of the WG hole so that air would flow better out of the WG hole by rounding the edges of the inside of the hole......works like a champ now and mine was already opened up to 1 1/8" before I opened it up more to controll boost but I have a small 31E exhaust wheel so it spools faster already than your average GT61.

 

[Spl170s]

if this is something i will have to do then...to control my creep issue.... can it be done wiht the exhaust housing still on the turbo? obviously dremeling is going to create some metal shavings......

AND, when feeling around in the opening on the tubro, the hole really doesn't have any material to take out toward the exhaust impeller. the hole kinda goes straaight back through the opening. kinda hard to explain i guess. basically there isn't jsut a thickness of material to cut away. it is solid back on the side that i need to remove material....

could i correct this issue with jsut using some sort of valve setup in line on the hoses from the turbo compressor....? thought i read somewhere that this helps?

RJC i think makes something?

 

[2QUIK6]

You can try the RJC spring/ball controller. I didn't have much luck with it but I was trying to run it in-line with the BstC controller..and this was after I had corrected my boost spike issue by porting out the hole...spike returned with the RJC part inline.
If you dremmel it, I would strongly recommend removing the turbo and/or the exhaust housing. I've gotten the housing off before without removing the entire turbo if you can get the 3-bolts completely out of the header that bolt to the exhaust housing and the exhausting to turbo center section bolts will come out...heat them up some before trying to remove or let the car run for a few minutes.

On smoothing out the inside of the WG hole....stick your finger into the hole from the side the DP would bolt to, feel the edge where the hole is inside, its a 90 degree sharp edge...its that edge that I'm talking about smoothing out as air will flow better around a smoothed edge rather than a 90 degree sharp edge....mainly on the edge that is closest to the header flange side.

 

[MSDGN]

John Craig sets all the wastegate holes in his turbos at exactly 1"...he said any bigger can cause problems with too much pressure against the puck and actually blowing it open especially on the bigger turbos...I've never had any problems with 1"...IMO I'd look elsewhere for your problem...

 

[2QUIK6]

Originally posted by MSDGN
John Craig sets all the wastegate holes in his turbos at exactly 1"...he said any bigger can cause problems with too much pressure against the puck and actually blowing it open especially on the bigger turbos...I've never had any problems with 1"...IMO I'd look elsewhere for your problem...

Good point I forgot about since I run a HD WG actuator as I always run over 19# of boost, but didn't really have an issue with the 13# actuator either but didn't run it very long.
Could have a bad WG solenoid, wrong size 'Y' fitting in vac lines to turbo/actuator, improperly installed vac lines in the same area.

 

[Spl170s]

i noticed that my hose connected to the wastegate solenoid is plumbed to the oppostie one of my friends buick....could this cause this problem?

Otherwise, my lines are all good and the y is in place like it should be.

i am thinking the same thing..... 1" seems pretty good size.......and the hole is practically centered.

Ther RJC might be something to look into then...as well as checking this solenoid plumbing....any thoughts on this?

 

[Ormand]

Either hole in the wastegate solenoid should work, since it just vents to the open air through the unused hole. BUT.. there may be a little more restriction to flow in one direction than in the other. I've never taken one of these solenoids aparts, so I'm not sure, but some valves have an "easy" direction and a "hard" direction. Good think is, it is real simpled to just move the hose and try it, see what happens. You might want to get a heavy duty solenoid, too. ATR, others have them, good for higher boost, bigger turbos. Anyway, that's what the catalogs say.